1. Field of the Invention
The present invention relates to an MPEG video decoding system with a PVR (Personal Video Recorder) function which is applied to the application fields of a digital TV (television receiver) or a digital video recorder.
2. Discussion of the Related Art
In the field of home appliances such as a digital TV, an MPEG (Moving Picture Experts Group) encoder is used in order to reduce storage and transmission capacity of a digital video or audio. Especially, the digital TV or an STB (Set-Top Box) provides various services of a PVR, and a storage medium used for such services is being changed from an analog type such as the existing VTR (Video Tape Recorder) to a digital type such as an HDD (Hard Disc Drive). Also, there is an increasing demand for a digital TV having a function of processing TV input signals of two or more channels such as a PIP (Picture-In-Picture) function, POP (Picture-On-Picture) function, etc.
The prior art appliances relating to the PVR function have been proposed as follows:
U.S. Pat. No. 6,215,526 assigned to TiVo Company first discloses a PVR device which encodes an analog signal to a digital signal and then stores the digital signal in an HDD by video-tagging the digital signal.
U.S. Pat. No. 6,351,596 discloses a PVR appliance which stores programs according to a user's preference based on a CPU (Central Processing Unit). This PVR appliance stores the program in the unit of a scene according to VBI (Vertical Blank Interval) data or a tagged code such as a code block and so on.
U.S. Pat. No. 6,327,418 discloses a function capable of separating digital data into a video segment, an audio segment, an MPEG system stream, etc., storing the divided data in a cache, and rapidly reproducing the video data at a predetermined rate through a cache control.
U.S. Pat. No. 6,324,338 assigned to replay TV discloses a system for using an integrated channel guide so as to store TV programs suitable for users' criteria.
According to the above-described techniques, however, in the case of simultaneously viewing high-quality images of two channels, viewing a TV program while storing another TV program corresponding to another channel, or viewing a TV program stored through a time shift function, respective chips, which satisfy various types of functions, should separately be prepared or should be used in combination.
Especially, the PVR chip and the video decoding chip are separately designed to perform the PVR function and the video decoding function, respectively, and this causes the system cost to increase and the system integration to deteriorate.